Awkward fastText dependency

Created by: bt2901

If you install everything from scratch via pip install deeppavlov, then it installs fasttext from PyPi. The problem is, in order to use fasttext you should import it as import fasttext, but deeppavlov uses import fastText internally.

If you install fasttext from GitHub first, then install deeppavlov via pip, then everything is OK (well, import fasttext fails but import fastText works)